Gut bacteria could affect development of age related diseases including type 2 diabetes

The composition of gut bacteria could affect the development of age-related diseases such as type 2 diabetes, according to new research.
The study, conducted by researchers from University of California Los Angeles (UCLA), could explain why some people remain healthy well into old age, while others develop serious diseases.
“Age-onset decline is very tightly linked to changes within the community of gut microbes,” said David Walker, UCLA professor of integrative biology and physiology, and senior author of the study.
“With age, the number of bacterial cells increase substantially and the composition of bacterial groups changes.”
The researchers analysed the intestinal tracts of fruit flies, examining the changes that occurred as the fruit flies aged. Fruit flies are useful for a study of this kind, because, although they only tend to live for eight weeks, there are large discrepancies in their lifespans. Some fruit flies live to the human equivalent of 90, some die much sooner. Fruit flies are also useful because they are well understood: research has worked out how to switch on and off all of the fruit fly’s individual genes.
The researchers analysed over 10,000 female fruit flies. They found that the fruit flies’ intestinal tracts leaked between five and six days before their death. It was possible to identify intestinal bacteria changes before any leaking began. Antibiotics reduced the amount of bacteria in the intestine, which improved the function of the intestines as the fruit flies aged.
“When we prevented the changes in the intestinal microbiota that were linked to the flies’ imminent death by feeding them antibiotics, we dramatically extended their lives and improved their health,” said Walker.
Those fruit flies treated with antibiotics lived on average 20 days longer after their intestines began to leak. The ones that weren’t given antibiotics usually died within a week of leakage.
Being able to predict health outcomes as people age could lead to better treatments, and new ways to prevent declining health in older people.
Several diseases have been linked to age-related bacterial changes, including type 2 diabetes and Parkinson’s disease. The problem is, researchers don’t yet know what healthy microbiota look like. Treatment for Alzheimer’s disease, heart disease and stroke could also benefit from the findings.
Lead author Rebecca Clark said: “The health of the intestine – in particular the maintenance of the barrier protecting the rest of the body from the contents of the gut – is very important and might break down with aging.”
The findings were published in Cell Reports.